COVID-19 is an emerging, rapidly evolving situation.

Get the latest public health information from CDC and research information from NIH.

U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Share This:
Study Information
Study Attribute Value
CEBS Accession Number: 002-01864-0012-0000-4
Chemical Name: Chlorobenzilate
CASRN: 510-15-6
NTP Study Type: Genetic Toxicology - Mammalian Cell Mutagenicity
NTP Study ID: 252225
Study Result: Positive


Table Instructions and Notes:
Studies are indicated to be "Nontoxic" when the observed reductions in relative total growth did not indicate that the maximum tolerated dose was achieved.

Nonactivation Trial: 1 Experiment Call: Positive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 50# 87 54 36 28
    64 101 44 23
    65# 113 48 25
    45r 86 36 27
Test Chemical Chlorobenzilate 
10         
 70 126 63 30 30
    84# 120 75 30
  
40         
 73# 106 63 29 35
    67 100 81 40
  
70         
 60 98 52 29 35
    65 78 81 42
  
100         
 76# 19 105 46 48*
    67 19 100 50
  
130         
   
Positive Control Methyl Methane Sulfonate 
15         
 20# 23 148.5 254 245*
    21# 24 148.5 236

Nonactivation Trial: 2 Experiment Call: Negative
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 81 101 81 33 40
    84 94 101 40
    78 108 96 41
    77 97 108 47
Test Chemical Chlorobenzilate 
20         
 92 119 87 32 34
    93 109 104 37
  
40         
 82 99 79 32 31
    78 98 72 31
  
60         
 99 84 67 23 27
    98 98 93 32
  
80         
 69 20 90 44 45
    74 23 104 47
  
100         
   
Positive Control Methyl Methane Sulfonate 
15         
 44 46 228 172 205*
    37 32 266 238

Nonactivation Trial: 3 Experiment Call: Positive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 81 98 103 42 32
    81 100 84 35
    87 104 71 27
    81 98 61 25
Test Chemical Chlorobenzilate 
50         
 78 85 76 32 32
    90 83 87 32
  
60         
 76 57 85 37 31
    71 52 54 26
  
70         
 76 27 91 40 45
    83 43 125 50
  
80         
 63 11 169 89 80*
    67 11 142 71
  
90         
 45 5 160 120 86*
    76 20 120 52
  
100         
   
Positive Control Methyl Methane Sulfonate 
15         
 42 17 222 178 157*
    41 24 169 136
Methyl Methane Sulfonate 
250         
 63 64 368 196 197*
    61 70 361 197

Induced S9 Trial: 1 Experiment Call: Inconclusive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 104 108 179 57 55
    96 94 173 60
    107 96 169 52
    116 102 169 48
Test Chemical Chlorobenzilate 
60         
 98 78 118 40 49
    87 97 150 57
  
70         
 86 74 186 72 74
    83 77 189 76
  
80         
 82 69 152 62 63
    83 65 159 64
  
90         
 95 46 151 53 56
    77 77 136 59
  
100         
 93 36 180 64 63
    84 33 156 62
Positive Control 3-Methylcholanthrene 
2.5       
 79 73 512 216 196*
    104 79 544 175

Induced S9 Trial: 2 Experiment Call: Inconclusive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 70 90 125 60 61
    87 104 147 56
    86 100 140 54
    78 106 167 72
Test Chemical Chlorobenzilate 
60         
 56 79 120 72 69
    72 83 141 65
  
70         
 54 80 147 91 82
    64 93 142 74
  
80         
 56 78 154 92 79
    60 77 120 67
  
90         
 72 67 146 68 71
    65 73 146 74
  
100         
 62 43 140 75 80
    72 49 182 85
Positive Control 3-Methylcholanthrene 
2.5       
 39 22 621 533 460*
    52 32 601 388

Induced S9 Trial: 3 Experiment Call: Positive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 77 104 95 41 46
    67 100 95 47
    75 92 121 54
    77 104 98 43
Test Chemical Chlorobenzilate 
70         
 71 57 130 61 80*
    69 46 203 98
  
80         
 74 51 170 77 91*
    61 44 190 104
  
90         
 57 16 318 187 164*
    71 21 299 141
  
100         
 50 11 359 238 274*
    53 8 494 310
  
110         
 57 12 261 153 268*
    37 4 425 383
Positive Control 3-Methylcholanthrene 
2.5       
 47 19 632 445 443*
    45 32 601 442

Induced S9 Trial: 4 Experiment Call: Positive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 85 110 104 41 44
    90# 111 127.5 47
    93 91 125 45
    100 88 136 45
Test Chemical Chlorobenzilate 
60         
 98 59 198 67 67
    91 63 181 67
  
70         
 88 52 181 68 75*
    101 45 247 82
  
80         
 74 29 247 111 131*
    86 30 389 151
  
90         
 77 9 718 311 288*
    71 13 563 264
  
100         
 64 5 1079 559 514*
    66 6 932 470
  
110         
   
Positive Control 3-Methylcholanthrene 
2.5       
 81 39 587 243 251*
    72 42 559 260

Footnotes:
Asterisks(*) indicate significant responses.
r = rejected value due to quality control criteria
# = reduced sample size because of the loss of one culture dish due to contamination